Feature Toggle Management Template

Use a feature toggle when you want to deploy code to production without exposing it, roll out gradually, or run an [A/B test](/glossary/a-b-testing). Use a feature branch when the work is too large to merge incrementally (rare). Feature branches that live longer than a week create merge conflicts and integration risk. Toggles let you merge to main daily while controlling exposure.

Environment variables work for simple on/off toggles, but they require a redeploy to change. A feature flag service lets you change toggle state instantly without deploying, target specific user segments, and run percentage-based rollouts. If your team deploys less than daily or needs segment-based targeting, invest in a flag service.

Test both states: toggle on and toggle off. Your test suite should include flag-specific tests that verify behavior in both states. When a toggle reaches 100% and is marked for cleanup, the "toggle off" tests become unnecessary. Remove them when you remove the toggle code.

Over time, forgotten toggles accumulate. Engineers avoid changing code near old toggles because they do not understand the flag's purpose. The codebase becomes harder to reason about. Schedule a quarterly toggle audit (see the audit summary section) and add toggle cleanup to your [definition of done](/templates/definition-of-done-template) for features.